Description: Studier Induction Media is based on Studier’s ZYP-5052 media1 and has been reformulated for ease of use. All of the ingredients are contained in 2 bottles instead of the usual 5. This medium should be used when stronger buffering is needed. This media contains high amounts of phosphate which reduces the selectivity of kanamycin. The amount of kanamycin (when appropriate) used should therefore be increased to at 200μg/ml.

At the time of usage, aseptically add 120mL of Studier Salts Solution (Cat. No.3S8600 120mL included) to Studier ZYP-5052 Medium for Induction. (Cat. No.3S8000 880mL included). Media is stable for 2 months once the salt solution has been added. Note: this media contains glucose, lactose, and glycerol as carbon sources. No further additions are required.

Induction media works with all T7 regulated E. coli vectors in BL21 and derivative strains.

When glucose is present in the media the expression of the lactose permease is inhibited and lactose will not be transported into the cell. After approximately 12 hrs of growth the glucose will be consumed and the lactose permease will begin to express thereby transporting lactose into the cells.

In strains such as BL21 the T7 RNA polymerase has been inserted into the chromosome and is under control of the lacUV5 promoter and is therefore inducible with lactose.
Genes cloned into vectors containing the T7 promoter (eg. pET
2 and Flexi®3 vectors) will not be expressed until all of the glucose in the media has been consumed.
This is very useful for protein production and generally results in significantly higher protein yields than is obtain in conventional media.